BEIJING (Reuters) - China’s agriculture ministry said on Tuesday that the country’s African swine fever outbreak remains complex and severe, and prevention and control efforts are in a pivotal period.

China has reported 28 cases of the highly contagious disease in eight provinces so far, the Ministry of Agriculture and Rural Affairs said in a statement published on its website. The country’s first African swine fever outbreak was found in the city of Shenyang in Liaoning province in early August.

Risks of transmission of the disease from overseas are still high, according to the statement.

China has recently confirmed six African swine fever cases in the city of Yingkou in Liaoning and the deadly disease is spreading in the region, the ministry said in another statement published on its website on Tuesday.

The comments came amid rising concerns that the deadly virus might spread rapidly in the world’s largest pig herds and beyond its borders to Southeast Asia.

China will take effective measures to stabilize pig production and hog circulation, and guarantee pork supplies to Hong Kong, Macau, Beijing, Shanghai and other major cities, the ministry said.